Conductor wire and circuit board. Since before 1980 technicians installing telephone and data circuits have terminated the ends of insulated wires in circuit boards having connectors of the insulation displacement type. Connectors of that type have electrical contact members which form a pair of blade-like cutting edges occupying a common plane with a V-shaped space between them. When the end of an insulated conductor wire is pushed down between the blade-like members, their sharp cutting edges cut through the insulation and sufficiently into the metal that the circuit board contact is then in electrically conductive engagement with the conductor wire. At the same time, some insulation surrounding the contact area is purposely left in place to protect the contacts against moisture.
Wire Termination Tool. It is standard practice to use a wire termination tool, which has a metal tool body that also carries a blade both for inserting the wire end between the connector contacts or alternatively for concurrently inserting the wire end between the connector contacts and cutting off a protruding end of the conductor wire. One standard type of such a wire termination tool is known as a “110 Blade”, and another standard type is known as a “66 Blade”. While those two types of tools are somewhat differently shaped to work with differently shaped connector panels, their function is essentially the same. The conductor wire to be attached to the connection panel is placed across the front of the 110 Blade or 66 Blade termination tool. The wire termination tool is then driven forward to insert the conductor wire between corresponding insulation displacement knife blade contacts and to seat the wire or to optimally seat the wire and concurrently cut off a protruding end of the wire.
Impact Driver or Punch-Down Tool. It has also been standard industry practice to use a hand-operated impact driver or punch-down tool for driving either a 110 Blade or a 66 Blade. The hand-operated driver or impact tool has a housing for slidably receiving the termination tool. The termination tool, whether a 110 Blade, 66 Blade, or other industry standard type blade, is slidably mounted within or upon the driver. The punch-down or impact driver tool contains an internal spring which becomes compressed when the tradesman or technician applies hand force. A factory setting on the impact tool allows a selection to be made of either a high or a low level of impact force.
Compression Spring Drive Action. A forward end of the conductor wire to be inserted into the connector panel is placed across the forward end of the wire termination tool. The forward or output end of the compression spring bears against the 110 Blade Tool, 66 Blade Termination Tool, or other industry standard termination tool. The technician or tradesman pushes the impact tool forward, and when the pre-set force level is reached a trigger associated with the spring then automatically releases the spring compression. The stored energy of the compression spring then drives the 110 or 66 Blade or other standard tool forward to insert the conductor wire into the connector of the circuit panel. At this time the technician or tradesman should be holding the impact tool steady, so as to achieve the exact impact for which the pre-set spring compression was selected. Typically, although not necessarily, the forward movement of the termination tool also concurrently cuts off a protruding end of the wire, by means of a cutting blade carried on the tool.
Abrupt release. Thus according to standard practice a spring that is manually compressed to a predetermined level is abruptly released by a mechanical trigger to drive the termination tool. The release of the spring force and its resulting momentum will then drive the termination tool member forward to seat the conductor wire within the connector and also to cut off its protruding end.
Optimum Contact. In the typical connectors of the insulation displacement type the pair of knife blades that achieve the electrical contact with a conductor wire inserted between them have certain characteristics. The blades are not entirely stiff and immobile, but are so constructed as to have a certain amount of spring action. Their configuration provides an optimum location where is it preferred to have the conductor lodge. This may be referred to as a “sweet spot”. But if a conductor wire is not inserted far enough to reach the “sweet spot” the electrical contact may be inferior. And if the conductor wire is pushed too far there may be significant damage to the connector or to the panel on which it is mounted. Desired product design is such that if a conductor is correctly inserted at the “sweet spot” it should be possible to remove that conductor and insert a different one, for dozens or perhaps hundreds of times, without damage to the connector panel. In some installations the conductor wire is electrically connected to the panel but does not need to be cut off, and remains an active electrical conductor in both directions from the connector panel.